Power allocation for cognitive users applying OFDM under dynamic spectrum activity

Abstract

In this paper a new and original approach for power allocation for cognitive users is proposed. The approach is based on the application of the order statistics (maximum terms of the variation series) for instantaneous SNR levels. Contrary to the widely applied methods, in the proposed approach, power is allocated to the groups of the OFDM sub-carriers which suffer the same flat fading. It is shown by means of an example how results of this method can be compared with the sub-optimum results of the nonlinear programming presented before.